1. Field of the Invention
This invention relates to a hydraulic intensification circuit using a rotary flow divider with a bypass valve.
2. Background Information
Hydraulic systems are popular in applications involving hazardous, dirty, and nasty environments, such as coal mines, quarries, food processing plants, and construction sites. Much effort has been expended in trying to increase the efficiency and performance ranges of hydraulic systems.
Intensification is a phenomena associated with rotary flow dividers, usually considered an undesirable phenomena to be guarded against and protected from, such as by incorporating pressure relief valves.
Although not in common usage, intensification from rotary flow dividers can be useful in some circumstances, such as when extra force from a cylinder or torque from a motor is required as a part of the duty cycle. Circuits useful is said circumstances are often referred to as high/low circuits or two speed circuits, and often involve double pumps.
A publication illustrating gerotor rotary flow dividers in intensification and multispeed circuits is the American Society of Agricultural Engineers Paper No. 911596 “Gerotor Rotary Flow Divider” by George Morgan, P.E., Sales Manager, White Hydraulics, Inc. presented at the 1991 International Winter Meeting sponsored by the American Society of Agricultural Engineers at the Hyatt Regency Chicago, Chicago, Ill., December, 1991 which is hereby incorporated by reference. The American Society of Agricultural Engineers is located at 2950 Niles Road, St. Joseph, Mich., 49085-9659, USA, Ph. (616) 429-0300, Fax: (616) 429-3852.
The state of the art uses flow dividers in intensification circuits where the flow divider is in constant operation. This contributes to system wear, wasted energy, and noise.
In multispeed circuits, where double or triple pumps are used, the pumps are in constant operation, which results in system wear, wasted energy, and noise. Also, pumps are relatively expensive as to compared to gerotor rotary flow dividers.
In previous patents awarded to applicant, U.S. Pat. No. 6,279,317 Morgan Aug. 28, 2001 and U.S. Pat. No. 6,438,951 Morgan Aug. 27, 2002, a valve means was used to isolate a flow divider in regenerations circuits. While it may be argued that based on those patents and the above mentioned ASAE technical paper, the material in this application is obvious to anyone skilled in the art, applicant, who is very skilled in the art, can assure the examiner that it wasn't obvious to the applicant.
As will be seen from the subsequent description, the preferred embodiments of the present invention broadens the performance range of a hydraulic drive while conserving energy, reducing componentry wear, and even, in some cases, with less noise.